scholarly journals A Teleconnection between Forced Great Plains Snow Cover and European Winter Climate

2008 ◽  
Vol 21 (11) ◽  
pp. 2466-2483 ◽  
Author(s):  
Nicholas P. Klingaman ◽  
Brian Hanson ◽  
Daniel J. Leathers
Keyword(s):  
Snow Cover ◽  
Great Plains ◽  
North American ◽  
The United States ◽  
Northern Great Plains ◽  
Late Winter ◽  
Winter Climate ◽  
Early Season ◽  
Late Season ◽  
The North

Abstract Anomalies in Siberian snow cover have been shown to affect Eurasian winter climate through the North Atlantic Oscillation (NAO). The existence of a teleconnection between North American snow cover and the NAO is far less certain, particularly for limited, regional snow cover anomalies. Using three ensembles of the Community Atmosphere Model, version 2 (CAM2), the authors examined teleconnections between persistent, forced snow cover in the northern Great Plains of the United States and western Eurasian winters. One ensemble allowed the model to freely determine global snow cover, while the other two forced a 72-cm snowpack centered over Nebraska. Of the forced ensembles, the “early-season” (“late season”) simulations initiated the snowpack on 1 November (1 January). The additional snow cover generated lower (higher) sea level pressures and geopotential heights over Iceland (the Azores) and warmer (cooler) temperatures over northern and western (eastern and southeastern) Europe, which suggests the positive NAO phase. Differences between the free-snow-cover and early-season ensembles were never significant until January, which implied either that the atmospheric response required a long lag or that the late-winter atmosphere was particularly sensitive to Great Plains snow. The authors rejected the former hypothesis and supported the latter by noting similarities between the early- and late-season ensembles in late winter for European 2-m temperatures, transatlantic circulation, and an NAO index. Therefore, a regional North American snow cover anomaly in an area of high inter- and intra-annual snow cover variability can show a stronger teleconnection to European winter climate than previously reported for broader snow cover anomalies. In particular, anomalous late-season snow in the Great Plains may shift the NAO toward the positive phase.

scholarly journals Cold Climate Winegrape Cultivar Sensitivity to Sulfur in the Northern Great Plains Region of the United States

2017 ◽  
Vol 27 (2) ◽  
pp. 235-239
Author(s):  
Nagehan D. Köycü ◽  
John E. Stenger ◽  
Harlene M. Hatterman-Valenti
Keyword(s):  
United States ◽  
Great Plains ◽  
The United States ◽  
Organic Production ◽  
Cold Climate ◽  
Future Research ◽  
Northern Great Plains ◽  
Research Station ◽  
Injury Incidence ◽  
The North

Elemental sulfur is commonly applied for powdery mildew (Erysiphe necator) protection on winegrape (Vitis sp.). The product may be used in a diversified, integrated disease management system to help prevent fungicide resistance to products with other modes of action. Additionally, sulfur may be used as a control option in organic systems. Applications of sulfur have been known to cause phytotoxic injury to susceptible winegrape cultivars, particularly those stemming from fox grape (Vitis labrusca) parentage. To improve recommendations to producers in the northern Great Plains region of the United States, a comparison of injury incidence and severity, as well as effects on yield characteristics was undertaken for 13 regional cultivars exposed to three sulfur rates (0, 2.4, and 4.8 lb/acre a.i.) at a North Dakota State University Research Station near Absaraka, ND. Overall, four cultivars (Bluebell, Baltica, Sabrevois, and King of the North) of the 13 cultivars tested showed phytotoxic symptoms. Injury severity and incidence of these cultivars differed between years and across rates. ‘Bluebell’ showed consistent and severe sulfur injury symptoms. Injury to the other three susceptible cultivars tended to vary by the given environment, with King of the North generally showing the lowest injury response. Injury symptoms were not found to be associated with the overall yield or cluster weight. Results suggest that alternative spray programs that exclude sulfur-based fungicides should be recommended for ‘Bluebell’, ‘Baltica’, ‘Sabrevois’, and ‘King of the North’, whereas sulfur-based fungicides may be applied to ‘Alpenglow’, ‘ES 12-6-18’, ‘Frontenac’, ‘Frontenac Gris’, ‘La Crescent’, ‘Marquette’, ‘Somerset Seedless’, ‘St. Croix’, and ‘Valiant’. Observations on fruit ripening in 2014 suggest that future research is needed to determine if a reduction of fruit quality may occur in some seasons with repeated sulfur applications or with successive annual sulfur applications for susceptible cultivars if used in an organic production system.

CRUSTAL ELECTRICAL CONDUCTIVITY ANOMALIES IN THE GREAT PLAINS PROVINCE OF THE UNITED STATES

Geophysics ◽  
1971 ◽  
Vol 36 (2) ◽  
pp. 382-395 ◽  
Author(s):  
H. Porath ◽  
A. Dziewonski
Keyword(s):  
United States ◽  
Electrical Conductivity ◽  
Great Plains ◽  
Gulf Coast ◽  
Small Variation ◽  
The United States ◽  
Northern Great Plains ◽  
The North ◽  
Induced Currents ◽  
Magnetometer Arrays

Magnetic disturbance fields were recorded during the spring and fall of 1969 with two magnetometer arrays in the Great Plains province of the United States. The purpose of these studies was to map magnetic variation anomalies arising from inhomogeneities of crustal electrical conductivity; we wished to find regions where plane layered models yield apparent resistivity curves that are adequate approximations to curves determined from magnetotelluric measurements. Variation anomalies were found to be related to lateral changes in electrical conductivity of the upper crust, changes associated with sedimentary features. In southeast Oklahoma, induced currents are concentrated in the conductivity sediments of the deep Anadarko basin. These currents give rise to attenuated vertical variation fields to the west and south of the basin and to enhanced vertical fields to the north and northeast. Reversed vertical fields are observed for stations in north central Texas, close to the Ouachita tectonic belt which separates Paleozoic sediments in West Texas from younger sediments in the Gulf Coast plains. This distribution of fields indicates concentration of induced currents in the highly conductive coastal plains sediments. A small variation anomaly is associated with the region of the midcontinent gravity high in the northern Great Plains. The anomaly is probably caused by currents in the sedimentary troughs on the steep flanks of the Precambrian basalts, which give rise to the gravity anomaly.

Biennial Wormwood (Artemisia biennis) Early-Season Control with Herbicides

2004 ◽  
Vol 18 (3) ◽  
pp. 611-618 ◽  
Author(s):  
Bradley E. Fronning ◽  
George O. Kegode
Keyword(s):  
United States ◽  
Soil Moisture ◽  
Great Plains ◽  
The United States ◽  
Northern Great Plains ◽  
Early Season ◽  
Herbicide Treatments ◽  
Moisture Conditions

Biennial wormwood has become a problem for soybean producers in the northern Great Plains of the United States. Research was conducted to evaluate control of biennial wormwood with preemergence (PRE) herbicides alone or followed by postemergence (POST) herbicides in 2000 and 2001 at Fargo, Leonard, and Wyndmere, ND. Favorable soil moisture conditions at Leonard resulted in continual emergence and greater densities of biennial wormwood, whereas the soil at Fargo and Wyndmere was dry and few biennial wormwood seedlings emerged at these locations. Biennial wormwood control with PRE herbicides was greater than 89% at Fargo and Wyndmere but was 80% or lower at Leonard. PRE biennial wormwood control was higher with flumetsulam than with sulfentrazone. When POST treatments were applied after PRE herbicides, biennial wormwood control 4 wk after treatment was 92% or better at Fargo and Wyndmere but was 76% or less at Leonard. The combination of PRE and POST herbicide treatments did not improve control greatly at Fargo or Wyndmere but at Leonard reduced the number of biennial wormwood plants.

Sensitivity to Horizontal Resolution in the AGCM Simulations of Warm Season Diurnal Cycle of Precipitation over the United States and Northern Mexico

2007 ◽  
Vol 20 (9) ◽  
pp. 1862-1881 ◽  
Author(s):  
Myong-In Lee ◽  
Siegfried D. Schubert ◽  
Max J. Suarez ◽  
Isaac M. Held ◽  
Arun Kumar ◽  
...  
Keyword(s):  
Great Plains ◽  
Diurnal Cycle ◽  
North American ◽  
General Circulation ◽  
Warm Season ◽  
The United States ◽  
Horizontal Resolution ◽  
Moist Convection ◽  
The North ◽  
Diurnal Cycle Of Precipitation

Abstract This study examines the sensitivity of the North American warm season diurnal cycle of precipitation to changes in horizontal resolution in three atmospheric general circulation models, with a primary focus on how the parameterized moist processes respond to improved resolution of topography and associated local/regional circulations on the diurnal time scale. It is found that increasing resolution (from approximately 2° to ½° in latitude–longitude) has a mixed impact on the simulated diurnal cycle of precipitation. Higher resolution generally improves the initiation and downslope propagation of moist convection over the Rockies and the adjacent Great Plains. The propagating signals, however, do not extend beyond the slope region, thereby likely contributing to a dry bias in the Great Plains. Similar improvements in the propagating signals are also found in the diurnal cycle over the North American monsoon region as the models begin to resolve the Gulf of California and the surrounding steep terrain. In general, the phase of the diurnal cycle of precipitation improves with increasing resolution, though not always monotonically. Nevertheless, large errors in both the phase and amplitude of the diurnal cycle in precipitation remain even at the highest resolution considered here. These errors tend to be associated with unrealistically strong coupling of the convection to the surface heating and suggest that improved simulations of the diurnal cycle of precipitation require further improvements in the parameterizations of moist convection processes.

scholarly journals Climatic Role of North American Low-Level Jets on U.S. Regional Tornado Activity

2012 ◽  
Vol 25 (19) ◽  
pp. 6666-6683 ◽  
Author(s):  
Scott J. Weaver ◽  
Stephen Baxter ◽  
Arun Kumar
Keyword(s):  
United States ◽  
Great Plains ◽  
North American ◽  
Decadal Variability ◽  
Principal Component ◽  
The United States ◽  
Northern Great Plains ◽  
Low Level ◽  
Sst Variability ◽  
Trend Pattern

Abstract Variability of springtime tornadic activity over the United States is assessed through the connectivity of preferred modes of North American low-level jet (NALLJ) variability to the local thermodynamic environment and remote SST variations. The link between regional tornado activity and NALLJ variability as diagnosed from a consistent reanalysis system (i.e., NCEP–NCAR) serves as dynamical corroboration in light of the inhomogeneous tornado database. The analysis reveals a multidecadal variation in the strength of the NALLJ–tornado connection, highlighted by tornado activity in the southern Great Plains region nearly doubling its correlation with NALLJ principal component 1 (PC 1) in recent decades. Locally, this is a result of a southward shift of NALLJ variability modes during the recent period. Motivated by these epochal shifts in NALLJ activity, a comparison of the early (1950–78) and late (1979–2010) tornado and NALLJ SST linkages indicates an Atlantic decadal SST variability influence during the early epoch, with Pacific decadal variability thereafter, highlighting the remote SST influence on the shifts in geographic placement and strength of NALLJ variability. The remote SST variability linkages further reveal that the observed global-scale SST trend pattern over the last 61 years may be contributing to a shift toward weaker tornadoes during spring in the northern Great Plains region. Tornado activity over the southeast region of the United States shows no such relationship to the SST trend pattern during spring, an immunity that is unexpected if spurious trends in the tornado database were influencing the SST linkage.

From Plows, Horses, and Harnesses to Precision Technologies in the North American Great Plains

2017 ◽  
Author(s):  
David E. Clay ◽  
Sharon A. Clay ◽  
Thomas DeSutter ◽  
Cheryl Reese
Keyword(s):  
Great Plains ◽  
Cover Crops ◽  
North American ◽  
Management Practices ◽  
Genetically Modified Organisms ◽  
Wildlife Habitat ◽  
Northern Great Plains ◽  
Rapid Decline ◽  
Soil Productivity ◽  
The North

Since the discovery that food security could be improved by pushing seeds into the soil and later harvesting a desirable crop, agriculture and agronomy have gone through cycles of discovery, implementation, and innovation. Discoveries have produced predicted and unpredicted impacts on the production and consumption of locally produced foods. Changes in technology, such as the development of the self-cleaning steel plow in the 18th century, provided a critical tool needed to cultivate and seed annual crops in the Great Plains of North America. However, plowing the Great Plains would not have been possible without the domestication of plants and animals and the discovery of the yoke and harness. Associated with plowing the prairies were extensive soil nutrient mining, a rapid loss of soil carbon, and increased wind and water erosion. More recently, the development of genetically modified organisms (GMOs) and no-tillage planters has contributed to increased adoption of conservation tillage, which is less damaging to the soil. In the future, the ultimate impact of climate change on agronomic practices in the North American Great Plains is unknown. However, projected increasing temperatures and decreased rainfall in the southern Great Plains (SGP) will likely reduce agricultural productivity. Different results are likely in the northern Great Plains (NGP) where higher temperatures can lead to increased agricultural intensification, the conversion of grassland to cropland, increased wildlife fragmentation, and increased soil erosion. Precision farming, conservation, cover crops, and the creation of plants better designed to their local environment can help mitigate these effects. However, changing practices require that farmers and their advisers understand the limitations of the soils, plants, and environment, and their production systems. Failure to implement appropriate management practices can result in a rapid decline in soil productivity, diminished water quality, and reduced wildlife habitat.

scholarly journals The Effects of Snow Cover on Midlatitude Cyclones in the Great Plains

2005 ◽  
Vol 6 (3) ◽  
pp. 263-279 ◽  
Author(s):  
N. Elguindi ◽  
B. Hanson ◽  
D. Leathers
Keyword(s):  
Snow Cover ◽  
Great Plains ◽  
Mesoscale Model ◽  
The United States ◽  
Lower Atmosphere ◽  
Northern Great Plains ◽  
State University ◽  
Moisture Advection ◽  
Penn State ◽  
Midlatitude Cyclones

Abstract The impacts of snow cover on the structure and intensity of midlatitude cyclones are examined. The fifth-generation Pennsylvania State University–National Center for Atmospheric Research (Penn State–NCAR) Mesoscale Model (MM5) was used to simulate eight synoptic events in which a well-developed cyclone moved across the central and northern Great Plains region of the United States. Two simulations were performed for each event: a control run with the actual snow cover and a perturbed run with an extensive snow cover. In all of the cases, increasing the snow cover, and thereby reducing the available potential energy, weakened the cyclones. Among the eight cases, the averaged minimum central low pressure of the cyclones in the perturbed runs was approximately 4 mb greater than the control cyclones. The reduction in temperature and moisture in the lower atmosphere was most pronounced in the warm sector, which significantly reduced the thermal and moisture gradients near the surface. This resulted in a weakening of the fronts, less convergence near the surface, and decreased precipitation. Averaged among the cases, the upward vertical velocity near the center of the low was about 3.5 cm s−1 less in the perturbed simulations. Accumulated vertically integrated rainwater was reduced by 0.64 × 109 m3 when averaged for all of the cases in the perturbed simulations. In addition, the weaker gradients across the surface fronts in the increased snow-covered simulations decreased thermal and moisture advection near the surface and may have contributed to limiting the cyclones’ intensification in some of the cases by dampening positive feedback processes between the surface and midtroposphere.

scholarly journals Progress in Diagnosing Primary Ciliary Dyskinesia: The North American Perspective

Diagnostics ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1278
Author(s):  
Michael Glenn O’Connor ◽  
Amjad Horani ◽  
Adam J. Shapiro
Keyword(s):  
Genetic Testing ◽  
North America ◽  
North American ◽  
Primary Ciliary Dyskinesia ◽  
Clinical Phenotype ◽  
The United States ◽  
Diagnostic Process ◽  
The North ◽  
Diagnostic Guideline ◽  
Ciliary Dyskinesia

Primary Ciliary Dyskinesia (PCD) is a rare, under-recognized disease that affects respiratory ciliary function, resulting in chronic oto-sino-pulmonary disease. The PCD clinical phenotype overlaps with other common respiratory conditions and no single diagnostic test detects all forms of PCD. In 2018, PCD experts collaborated with the American Thoracic Society (ATS) to create a clinical diagnostic guideline for patients across North America, specifically considering the local resources and limitations for PCD diagnosis in the United States and Canada. Nasal nitric oxide (nNO) testing is recommended for first-line testing in patients ≥5 years old with a compatible clinical phenotype; however, all low nNO values require confirmation with genetic testing or ciliary electron micrograph (EM) analysis. Furthermore, these guidelines recognize that not all North American patients have access to nNO testing and isolated genetic testing is appropriate in cases with strong clinical PCD phenotypes. For unresolved diagnostic cases, referral to a PCD Foundation accredited center is recommended. The purpose of this narrative review is to provide insight on the North American PCD diagnostic process, to enhance the understanding of and adherence to current guidelines, and to promote collaboration with diagnostic pathways used outside of North America.

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